The temperature that must be to freeze the solution would be -21.1 ° C.
<h3>How to calculate the freezing temperature of this solution?</h3>
To calculate the freezing temperature we must take into account the following information.
- Solution with a salt concentration of 10% is frozen at -6°C
- Solution with a salt concentration of 20% is frozen at -16°C
- Solution with a higher concentration is frozen at -21.1°C
According to the above, it can be inferred that the puddle has a 50% concentration of salt because they had 12 kg of water and 6 kg of salt.
So the lowest freezing temperature would be 21.1°C because the puddle is 50% concentrated.
Note: This question is incomplete because there is some missing information. Here is the missing information:
- A 10% salt solution freezes at about 20°F (-6°C), and a 20% solution freezes at 2°F (-16°C).
- The lowest freezing point obtainable for salt solutions is −21.1 °C
Learn more about freezing in: brainly.com/question/14131507
Answer:
6.53g of K₂SO₄
Explanation:
Formula of the compound is K₂SO₄
Given parameters:
Volume of K₂SO₄ = 250mL = 250 x 10⁻³L
= 0.25L
Concentration of K₂SO₄ = 0.15M or 0. 15mol/L
Unknown:
Mass of K₂SO₄ =?
Methods:
We use the mole concept to solve this kind of problem.
>>First, we find the number of moles using the expression below:
Number of moles= concentration x volume
Solving for number of moles:
Number of moles = 0.25 x 01.5
= 0.0375mole
>>Secondly, we use the number of moles to find the mass of K₂SO₄ needed. This can be obtained using the expression below:
Mass(g) = number of moles x molar mass
Solving:
To find the molar mass of K₂SO₄, we must know the atomic mass of each element in the compound. This can be obtained using the periodic table.
For:
K = 39g
S = 32g
O = 16g
Molar mass of K₂SO₄ = (39x2) + 32 + (16x4)
= 78 +32 + 64
= 174g/mol
Using the expression:
Mass(g) = number of moles x molar mass
Mass of K₂SO₄ = 0.0375 x 174 = 6.53g
